Is the Covid-19 pandemic over? The answer is more art than science

Is the Covid-19 pandemic over?

President Biden told Scott Pelley of “60 Minutes” it was. The Sunday night interview aired just days after the director-general of the World Health Organization, Tedros Adhanom Ghebreyesus, said the end may be in sight — though Tedros clearly didn’t mean it was days away when he predicted it.

But how confident can we be that the pandemic is or will soon be over? How can we know we’ve reached “over” when the disease we’ve been fighting isn’t going away?

Reaching the end of a pandemic is not like driving out of one county into the next. There is no fixed demarcation between a pandemic and post-pandemic period, especially for the first recorded pandemic caused by a coronavirus. It’s not like we know it’s over if cases drop to a certain level for a prescribed length of time.

Experts say there are no accepted metrics or defined international rules that tell us when we can call the code on this horrible event. In reality, things are much more ephemeral when it comes to knowing when a pandemic is over.

“It’s over when people decide that it’s over. … And most people seem to have decided it’s over,” said John Barry, author of “The Great Influenza,” a history of the 1918 Spanish flu.

Most of the experts who spoke with STAT echoed a version of Barry’s remarks: In some respects, the pandemic is over when people stop taking measures to protect themselves, when they stop following advice about how to lower their risk, when they resume pre-pandemic behavior.

Michael Osterholm, director of the University of Minnesota’s Center for Infectious Disease Research and Policy, said there are actually a couple of ways to think about when a pandemic ends: by looking at what the disease is doing to humans physically and psychologically.

By the latter yardstick, the pandemic is done like dinner.

“Everyone right now is fairly focused on the psyche. They want to move on. They’re done with the pandemic. And I think that [Biden’s] comment reflects that,” Osterholm said.

Using the former yardstick, however, Osterholm would disagree — noting pandemic deaths have risen in recent weeks and the disease is still the fourth-leading cause of death in the country.

“We’ve been in this high-plains plateau for 12 weeks. I don’t know how anyone can say the pandemic is over for that reason,” he said. “In addition, we don’t yet know what the next shoe to drop is.”

Osterholm suggested there was no science bolstering the president’s statement, calling it “an unfortunate unforced error” coming as it did while the administration is trying to drive up acceptance of the new updated Covid vaccines.

“The last thing you want to do is discourage people from getting their boosters. If I hear the president of the United States say the pandemic is over, why in hell would you want to get a booster?” he asked.

Some people might assume the WHO will issue a decree of sorts, an all-clear declaration. But in reality that’s not something the global health agency does, said Alexandra Phelan, an assistant professor at Georgetown University’s Center for Global Health Science and Security. The WHO didn’t declare the start of the pandemic and it won’t declare an end to it, she said.

At some point, however, the WHO will announce the lifting of the state of emergency it declared in late January of 2020 when Tedros declared the new disease constituted a public health emergency of international concern, or PHEIC, as the instrument is known in public health circles. The director-general seeks advice from a committee of outside experts on issues related to the PHEIC; that committee must meet at least every three months, though it could meet sooner if Tedros asked it to.

The Covid emergency committee last met on July 8, which means an early October meeting must be held. Phelan doesn’t think the committee will advise calling off the PHEIC at that point, though she thinks conditions may allow for it toward the end of the year.

The U.S. government also has an emergency declaration in effect, a tool that gives it powers that have eased its ability to enact policies, allocate funding, and fast-track the authorization of Covid vaccines, drugs, and tests. At some point it will be declared at an end, but that is not what Biden was signaling in the “60 Minutes” interview.

The Department of Health and Human Services has said it will give a 60-day notice to states before it terminates the public health emergency, or allows it to expire. The next date for extending the emergency declaration is in October.

J. Alexander Navarro, assistant director of the University of Michigan’s Center for the History of Medicine, said many of the terms the public has gotten accustomed to hearing over the past couple of years — outbreak, epidemic, pandemic, endemic — are not well-defined.

The reality is pandemics are rare events, and each is distinct. The 1918 pandemic was characterized by three waves — though Barry now believes there was actually a fourth in the United States, in 1920, with some cities experiencing more deaths than during the fall wave of 1918. The 2009 H1N1 pandemic, which was mild by pandemic standards, had a single wave.

Typically it has taken the passage of time to see that another wave didn’t crest, that disease activity had returned to a normal pattern. That’s easier to see in retrospect than in real time.

It’s especially hard this time, Navarro said, because of our lack of recorded experience with pandemics caused by coronaviruses. There are four coronaviruses that cause common colds; they too at one point made their way from an animal source into people. But it’s not known when that happened. And if they triggered what we would consider a pandemic when they did so, the events were likely mistaken for influenza.

With flu pandemics, the transition into the post-pandemic period is deemed to have occurred when flu activity resumes its normal cadence. Summer waves disappear; activity — at least in temperate zones — peaks during the winter months. Deaths decline. Unusual behavior gives way to usual behavior.

There’s a problem here: We don’t yet know what endemic Covid-19 is going to look like.

“What is normal going to look like with Covid? How many cases are we going to expect daily, seasonally, yearly?” Navarro asked.

Osterholm said there should be some ground rules established for when and how to declare the pandemic over, noting that if things take a turn for the worse, public trust will take another beating.

“You can’t make a pandemic go away by a policy decision,” said Osterholm. “It doesn’t work.”

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